Salifert manufactures titration test kits for the full range of reef chemistry parameters: alkalinity, calcium, magnesium, phosphate, nitrate, ammonia, copper, iodine, potassium, and more. Salifert kits are accurate, well-priced, and widely used by serious reefers.
The "big three" reef chemistry kits. Each provides 50-100 tests at $15-25 per kit. Accurate to 0.1 dKH (alk), 5 ppm (cal), 10 ppm (mg).
Color-comparator phosphate test reading 0.03-3.0 ppm. Less precise than a Hanna Checker but adequate for monitoring trends.
The most accurate magnesium hobby test kit available. Used as the reference test by many serious reefers.
Hanna Instruments (digital) · Red Sea (titration) · API (entry-level only)